Top dressed plating surface with resilient underpad

Abstract

A playing surface for athletic games comprising a stable subsurface, a resilient underpad of specified character, a pile fabric resembling grass and a sand top dressing. The inventive surface is particularly suited for use as a golf green which properly facilitates control of an approach shot and also provides a true putting surface. The playing surface simulates the feel and appearance of natural turf, but has much greater durability and requires less maintenance. By appropriately varying the construction of the surface, it is possible to control its character to provide for a desired type of play.

I claim: 
     
       1. A golf green comprising: (a) a firm, stable subsurface;   (b) a resilient, compressible underpad from 1/4 to 11/4" thick and having a density from about 3.5 to 12 lbs. per cubic foot;   (c) a pile fabric having a flexible backing and normally upstanding pile elements resembling grass; the length of said pile elements being substantially uniform and lying in the range from 1/2 to 11/2"; and   (d) a compacted top dressing layer of sand having a particle size in the range from 10 to 200 U.S. screen mesh interspersed among the pile elements and on the backing to a substantially uniform depth at least 1/2 the length of the pile elements;   the combination of subsurface, underpad, pile fabric and top dressing providing natural footing for players and facilitating ball control by dissipating the shock of objects impacting on the surface.   
     
     
       2. A golf green according to claim 1, wherein the pile fabric has a tuft density in the range from 10 to 16 tufts per square inch. 
     
     
       3. A golf green according to claim 2, wherein said underpad is a 1/2" thick layer of rebonded urethane foam having a density of 10 lbs. per cubic foot; a compression factor of 99 lbs., and said pile fabric is a tufted pile fabric having a tuft density of 13.3 piles per square inch, the length of the pile elements being 3/4" long and the projection of the pile elements above the top dressing being approximately 3/16". 
     
     
       4. A playing surface as recited in claim 1 further coprising at least one moisture barrier adjacent the underpad. 
     
     
       5. A playing surface as recited in claim 4 wherein said moisture barrier is disposed between the subsurface and the underpad. 
     
     
       6. A playing surface as recited in claim 5 wherein said moisture barrier is a layer of 30 to 100 lb. weight asbestos roofing felt. 
     
     
       7. A playing surface as recited in claim 4 wherein said moisture barrier is disposed between said underpad and said pile fabric. 
     
     
       8. A method as recited in claim 7 wherein said moisture barrier comprises a polyvinyl chloride coating on the underside of the pile fabric backing. 
     
     
       9. A playing surface as recited in claim 4 wherein said moisture barrier is a 2 to 10 mil thick polyethylene sheet. 
     
     
       10. A playing surface as recited in claim 1 wherein said underpad is a high-density polymeric foam having a density of at least 3.5 lbs. per cubic foot. 
     
     
       11. A playing surface as recited in claim 10 wherein said underpad is a high-density polymeric foam having a density between 8 and 12 lbs. per cubic foot and a compression factor between 75 and 130 lbs. 
     
     
       12. A playing surface as recited in claim 1 wherein said pile fabric is a tufted pile fabric. 
     
     
       13. A playing surface as recited in claim 12 wherein the backing of said tufted pile fabric is a woven polypropylene fabric and the tufts are formed from polypropylene ribbons slit and twisted to form a multifiliment yarn; each end of said yarn comprising from 20 to 50 individual pile filaments; the density of said tufts on said backing ranging between 8 and 24 tufts per square inch. 
     
     
       14. A playing surface as recited in claim 13 wherein said pile fabric is heat treated to slightly crimp the free ends of the pile filaments thereby to enhance the texture of the pile fabric. 
     
     
       15. A playing surface as recited in claim 1 wherein said top dressing comprises 20 to 50% sand having a particle size from 10 to 40 U.S. screen mesh; 30 to 60% sand having a particle size from 40 to 70 U.S. screen mesh, and 20 to 50% sand having a particle size from 70 to 200 U.S. screen mesh. 
     
     
       16. A playing surface as recited in claim 1 wherein the surface layer of said top dressing comprises predominantly sand having a particle size between 10 and 40 U.S. screen mesh. 
     
     
       17. A playing surface as recited in claim 1 wherein said underpad comprises a 14" thick layer of foam having a density of 20 lbs. per cubic foot and said pile fabric is a tufted pile fabric having a tuft density of 18.6 tufts per square inch; the length of the pile elements being 3/4" and the projection of the tips of the pile elements above the top dressing being approximately 1/16". 
     
     
       18. A playing surface as recited in claim 1 wherein the projection of the tips of the piles of the pile fabric above the top dressing lies in the range from 1/4 to 1/64".